1. Helicopter, as one of the most distinctive creations of aviation technology in the 20th century, has greatly expanded the application scope of aircraft. Helicopter is a typical dual-use product, which can be widely used in transportation, patrol, tourism, ambulance and other fields.
2. The maximum speed of a helicopter can reach more than 300km/h, the dive limit speed is nearly 400km/h, the service ceiling can reach 6000 meters (the world record is 12450m), and the general range can reach about 600 ~ 800 km. The range of internal and external auxiliary fuel tanks can reach more than 2000 kilometers. Helicopters have different takeoff weights according to different needs. At present, the largest heavy helicopter put into use in the world is the Russian Mi -26 (with a maximum takeoff weight of 56t and a payload of 20t). At present, there are mechanically driven single-rotor helicopters and double-rotor helicopters in actual use, of which single-rotor helicopters have the largest number.
3. The outstanding feature of the helicopter is that it can do low altitude (a few meters above the ground), low speed (from hovering) and the nose direction remains unchanged, especially suitable for small-area vertical take-off and landing. Because of these characteristics, it has broad uses and development prospects. In the military field, it has been widely used in ground attack, aircraft take-off and landing, weapons delivery, logistics support, battlefield rescue, reconnaissance patrol, command and control, communication, anti-submarine mine clearance, electronic countermeasures and so on. Used for short-distance transportation, medical rescue, disaster relief and lifesaving, emergency rescue, lifting equipment, geological exploration, forest protection and fire fighting, aerial photography, etc. The transportation of people and materials between offshore oil wells and bases is an important aspect of civil use.
4. Compared with fixed-wing aircraft, the current helicopter has more vibration and noise, more maintenance workload, higher use cost, lower speed and shorter flight range. The future development direction of helicopters is to improve these aspects.